Li Mengjiao, Lin Che-Yi, Chang Yuan-Ming, Yang Shih-Hsien, Lee Mu-Pai, Chen Ciao-Fen, Lee Ko-Chun, Yang Feng-Shou, Chou Yi, Lin Yi-Chun, Ueno Keiji, Shi Yumeng, Chou Yi-Chia, Tsukagoshi Kazuhito, Lin Yen-Fu
Department of Physics, National Chung Hsing University, Taichung 40227, Taiwan.
International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of the Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen 518060, China.
ACS Appl Mater Interfaces. 2020 Sep 23;12(38):42918-42924. doi: 10.1021/acsami.0c09922. Epub 2020 Sep 14.
Flexible manipulation of the carrier transport behaviors in two-dimensional materials determines their values of practical application in logic circuits. Here, we demonstrated the carrier-type manipulation in field-effect transistors (FETs) containing α-phase molybdenum ditelluride (MoTe) by a rapid thermal annealing (RTA) process in dry air for hole-dominated and electron-beam (EB) treatment for electron-dominated FETs. EB treatment induced a distinct shift of the transfer curve by around 135 V compared with that of the FET-processed RTA treatment, indicating that the carrier density of the EB-treated FET was enhanced by about 1 order of magnitude. X-ray photoelectron spectroscopy analysis revealed that the atomic ratio of Te decreased from 66.4 to 60.8% in the MoTe channel after EB treatment. The Fermi level is pinned near the new energy level resulting from the Te vacancies produced by the EB process, leading to the electron-dominant effect of the MoTe FET. The electron-dominated MoTe FET showed excellent stability for more than 700 days. Thus, we not only realized the reversible modulation of carrier-type in layered MoTe FETs but also demonstrated MoTe channels with desirable performance, including long-term stability.
灵活操控二维材料中的载流子输运行为决定了它们在逻辑电路中的实际应用价值。在此，我们通过在干燥空气中进行快速热退火（RTA）处理来实现空穴主导的含α相二碲化钼（MoTe）的场效应晶体管（FET）中的载流子类型操控，以及通过电子束（EB）处理来实现电子主导的FET。与经过RTA处理的FET相比，EB处理使转移曲线明显偏移了约135 V，这表明经过EB处理的FET的载流子密度提高了约1个数量级。X射线光电子能谱分析表明，EB处理后MoTe沟道中Te的原子比从66.4%降至60.8%。费米能级被钉扎在由EB过程产生的Te空位所导致的新能级附近，从而导致MoTe FET的电子主导效应。电子主导的MoTe FET在700多天内表现出优异的稳定性。因此，我们不仅实现了层状MoTe FET中载流子类型的可逆调制，还展示了具有理想性能（包括长期稳定性）的MoTe沟道。
